阅读说明：本技术 一种芳烃汽提塔酸性水回收利用系统 (Aromatic hydrocarbon stripping tower acid water recycle system ) 是由 刘丰敏 夏飞飞 唐远金 于 2020-04-29 设计创作，主要内容包括：本发明涉及一种芳烃汽提塔酸性水回收利用系统,包括酸性水预处理系统、酸性水汽提系统和氨气处理系统；酸性水预处理系统包括通过管线依次连接的原料酸性水过滤器、原料酸性水脱气罐、原料酸性水罐、原料酸性水加压泵、原料酸性水除油器、原料酸性水缓冲罐和原料酸性水进料泵；酸性水汽提系统包括冷进料冷却器、一级换热器、一级冷凝冷却器、二级换热器、重沸器和汽提塔；氨气处理系统包括通过管线依次连接的一级分凝器、二级冷凝冷却器、二级分凝器、三级冷凝冷却器、三级分凝器、氨水混合器、氨水冷却器和氨水罐。本发明具有减轻操作环境污染、充分利用低温热和能耗低等有益效果。(The invention relates to an aromatic hydrocarbon stripping tower acid water recycling system, which comprises an acid water pretreatment system, an acid water stripping system and an ammonia gas treatment system; the acidic water pretreatment system comprises a raw material acidic water filter, a raw material acidic water degassing tank, a raw material acidic water pressure pump, a raw material acidic water deoiler, a raw material acidic water buffer tank and a raw material acidic water feeding pump which are sequentially connected through pipelines; the acidic water stripping system comprises a cold feed cooler, a primary heat exchanger, a primary condensing cooler, a secondary heat exchanger, a reboiler and a stripping tower; the ammonia gas treatment system comprises a first-stage dephlegmator, a second-stage condensing cooler, a second-stage dephlegmator, a third-stage condensing cooler, a third-stage dephlegmator, an ammonia water mixer, an ammonia water cooler and an ammonia water tank which are sequentially connected through pipelines. The invention has the advantages of reducing the environmental pollution of operation, fully utilizing low-temperature heat, having low energy consumption and the like.)

1. The utility model provides an aromatic hydrocarbon stripper acid water recycle system which characterized in that: the recycling system comprises an acidic water pretreatment system, an acidic water stripping system and an ammonia gas treatment system; the acidic water pretreatment system comprises a raw material acidic water filter (1), a raw material acidic water degassing tank (2), a raw material acidic water tank (3), a raw material acidic water pressure pump (4), a raw material acidic water deoiler (5), a raw material acidic water buffer tank (6) and a raw material acidic water feed pump (7) which are sequentially connected through pipelines, wherein the output end of the raw material acidic water feed pump (7) is connected to the acidic water stripping system; the acidic water stripping system comprises a cold feed cooler (8), a primary heat exchanger (9), a primary condensation cooler (10), a secondary heat exchanger (11), a reboiler (12) and a stripping tower (13), the output end of a raw material acidic water feed pump (7) is connected with a cold feed pipeline (14) and a hot feed pipeline (15), the cold feed pipeline (14) is connected with the top of the stripping tower (13), the hot feed pipeline (15) is connected with the middle part of the stripping tower (13), the cold feed cooler (8) is arranged on the cold feed pipeline (14), the primary heat exchanger (9), the primary condensation cooler (10) and the secondary heat exchanger (11) are sequentially arranged on the hot feed pipeline (15), the reboiler (12) is arranged at the lower part of the stripping tower (13), a lateral line outlet of the stripping tower (13) is connected with the primary condensation cooler (10), the output end of the primary condensation cooler (10) is connected to an ammonia gas treatment system; the ammonia gas treatment system comprises a first-stage dephlegmator (16), a second-stage condensation cooler (17), a second-stage dephlegmator (18), a third-stage condensation cooler (19), a third-stage dephlegmator (20), an ammonia water mixer (21), an ammonia water cooler (22) and an ammonia water tank (23) which are sequentially connected through pipelines, and ammonia water is discharged through an ammonia water pump (24) at the outlet of the ammonia water tank (23).

2. The aromatics stripper sour water recycle system of claim 1, wherein: and the light oil gas removed from the raw material acidic water degassing tank (2) is discharged to a low-pressure gas pipe network.

3. The aromatics stripper sour water recycle system of claim 2, wherein: the acid water pretreatment system still includes sump oil processing apparatus, sump oil processing apparatus includes sump oil jar (25) and sump oil pump (26), the sump oil export of raw materials acid water degassing tank (2), raw materials acid water jar (3) and raw materials acid water degreaser (5) all with sump oil jar (25) access connection, light sump oil in sump oil jar (25) passes through sump oil pump (26) and discharges.

4. The aromatics stripper sour water recycle system of claim 3, wherein: the acid water pretreatment system further comprises a first water seal device, wherein the first water seal device comprises a raw material acid water seal device (27) and an adsorption tank (28), the raw material acid water seal device (27) is arranged at the tops of the raw material acid water tank (3) and the raw material acid water buffer tank (6), and the adsorption tank (28) is communicated with the raw material acid water seal device (27).

5. The aromatics stripper sour water recycle system of claim 1, wherein: the heat medium of the reboiler (12) is 1.0MPa steam, the 1.0MPa steam enters from the heat medium inlet of the reboiler (12), and the steam after heat exchange flows out from the condensed water outlet of the reboiler (12) to the condensed water tank (29).

6. The aromatics stripper sour water recycle system of claim 5, wherein: acid gas in the stripping tower (13) is discharged from the top of the stripping tower (13), and purified water in the stripping tower (13) passes through the secondary heat exchanger (11), the primary heat exchanger (9), the purified water air cooler (30) and the purified water cooler (31) in sequence after being discharged from the bottom of the stripping tower (13).

7. The aromatics stripper sour water recycle system of claim 1, wherein: and the dephlegmation liquid outlets of the first dephlegmator (16) and the second dephlegmator (18) are both connected with a dephlegmation liquid cooler (32), and the dephlegmation liquid outlets of the dephlegmation liquid cooler (32) and the third dephlegmator (20) are both connected with a raw material acid water tank (3).

8. The aromatics stripper sour water recycle system of claim 7, wherein: and one part of the crude ammonia gas discharged from the three-stage partial condenser (20) is discharged to a tail gas incinerator of a sulfur recovery device for incineration, and the other part of the crude ammonia gas is prepared into ammonia water through an ammonia water mixer (21) and an ammonia water cooler (22) and then flows to an ammonia water tank (23).

9. The aromatics stripper sour water recycle system of claim 8, wherein: one part of the ammonia water in the ammonia water tank (23) is discharged through the ammonia water pump (24), and the other part of the ammonia water flows to the ammonia water preparation pump (33); a part of the ammonia water discharged from the outlet of the ammonia water preparation pump (33) is discharged to the ammonia water mixer (21), and the other part is discharged to the raw material acidic water tank (3).

10. The aromatics stripper sour water recovery system of claim 9, wherein: the top of ammonia jar (23) is provided with second water seal arrangement, second water seal arrangement is ammonia water seal ware (34).

Technical Field

The invention relates to an acidic water treatment system, in particular to an aromatic hydrocarbon stripping tower acidic water recycling system, and belongs to the technical field of petrochemical industry.

Background

Sulfur-containing compounds and nitrogen-containing compounds are present in petroleum and its products, as is customaryDuring the processes of vacuum distillation, catalytic cracking, reforming, coking, hydrocracking, hydrofining, sulfur recovery and the like, the compounds can generate H through reactions such as pyrolysis, catalytic cracking, catalytic hydrogenation and the like₂S and NH₃And then the product stream is subjected to condensation dehydration or water washing to generate a large amount of acidic water.

The acidic water is a water containing H₂S，NH₃And CO₂The aqueous solution of the volatile weak electrolyte contains phenol, cyanide, oil and other pollutants, and the direct discharge can cause great harm to the environment, so the pollutants in the water can be discharged only after the pollutants reach a certain standard after being treated. The acidic water treatment in China mostly adopts a steam stripping method, which is called acid water stripping, also called acidic water stripping, and the common processes comprise single-tower pressurized side-draw stripping, single-tower low-pressure stripping, single-tower pressurized stripping and double-tower pressurized stripping.

However, the existing acidic water treatment process still has some defects, if the content of pollutants in the acidic water, such as ammonia, hydrogen sulfide, organic sulfide, volatile organic compounds and other malodorous media, is too much, the pollutants can escape from the acidic water tank and be discharged into the atmosphere to pollute the operating environment, the energy consumption of the existing double-tower steam stripping is too high, in addition, the heat exchange process of the commonly used acidic water treatment process is not good, and low-temperature heat is not fully utilized.

Disclosure of Invention

The invention mainly aims at the problems of operation environment pollution, overhigh energy consumption and low-temperature heat utilization rate in the existing acidic water treatment process, and provides an aromatic hydrocarbon stripper acidic water recycling system which adopts a single-tower pressurization side-draw steam stripping process, reduces the energy consumption by more than 40 percent compared with double-tower steam stripping, adopts a water seal and an adsorption tank in the acidic water pretreatment process to seal the discharge of harmful gas and adsorb malodorous components in released gas so as to reduce the pollution of the operation environment, and reasonably arranges a heat exchange process, wherein raw material acidic water hot feed enters the steam stripping tower after the primary heat exchange of purified water, the side-draw heat exchange and the secondary heat exchange of purified water reach about 150 ℃, so that the low-temperature heat is fully utilized.

The purpose of the invention is mainly realized by the following scheme:

an aromatic hydrocarbon stripping tower acid water recycling system comprises an acid water pretreatment system, an acid water stripping system and an ammonia gas treatment system; the acidic water pretreatment system comprises a raw material acidic water filter, a raw material acidic water degassing tank, a raw material acidic water pressurizing pump, a raw material acidic water deoiler, a raw material acidic water buffer tank and a raw material acidic water feeding pump which are sequentially connected through pipelines, wherein the output end of the raw material acidic water feeding pump is connected to the acidic water stripping system; the acidic water stripping system comprises a cold feed cooler, a primary heat exchanger, a primary condensation cooler, a secondary heat exchanger, a reboiler and a stripping tower, wherein the output end of a raw material acidic water feed pump is connected with a cold feed pipeline and a hot feed pipeline, the cold feed pipeline is connected with the top of the stripping tower, the hot feed pipeline is connected with the middle part of the stripping tower, the cold feed cooler is arranged on the cold feed pipeline, the primary heat exchanger, the primary condensation cooler and the secondary heat exchanger are sequentially arranged on the hot feed pipeline, the reboiler is arranged at the lower part of the stripping tower, a side line outlet of the stripping tower is connected with the primary condensation cooler, and the output end of the primary condensation cooler is connected to an ammonia gas treatment system; the ammonia gas treatment system comprises a first-stage dephlegmator, a second-stage condensation cooler, a second-stage dephlegmator, a third-stage condensation cooler, a third-stage dephlegmator, an ammonia water mixer, an ammonia water cooler and an ammonia water tank which are sequentially connected through pipelines, and ammonia water is discharged through an ammonia water pump at the outlet of the ammonia water tank.

By adopting the technical scheme, acid water from the outside of the device enters a raw material acid water degassing tank through a raw material acid water filter, the degassed acid water firstly enters a raw material acid water tank for sedimentation and deoiling, then enters a raw material acid water deoiler for further deoiling after being pressurized by a raw material acid water pressurizing pump, enters a raw material acid water buffer tank after deoiling, is pressurized by a raw material acid water feeding pump, a part of raw material water is cooled by a cold feeding cooler on a cold feeding pipeline and then is used as cold feeding of a stripping tower, the rest of raw material water passes through a primary heat exchanger on a hot feeding pipeline, a primary condensing cooler and a secondary heat exchanger and then is used as hot feeding to the stripping tower, purified water at the bottom of the stripping tower exchanges heat with the raw material acid water and then is sent to the outside of the device, stripping acid gas at the top of the stripping tower is sent to a sulfur recovery part, crude ammonia gas extracted from a side line, Separating condensate by a first-stage dephlegmator, cooling by a second-stage condensing cooler, separating condensate by a second-stage dephlegmator, cooling by a third-stage condensing cooler, and separating condensate by a third-stage dephlegmator to prepare ammonia water.

Preferably, the light oil gas removed from the raw material acidic water degassing tank is discharged to a low-pressure gas pipe network.

Through adopting above-mentioned technical scheme, the light oil gas that deviates from in the raw materials acid water degassing tank is sent to whole factory low pressure gas pipe network or gas holder, is carried out gas recovery and desulfurization treatment by whole factory unification.

Preferably, the acid water pretreatment system further comprises a dirty oil treatment device, the dirty oil treatment device comprises a dirty oil tank and a dirty oil pump, dirty oil outlets of the raw material acid water degassing tank, the raw material acid water tank and the raw material acid water oil remover are all connected with an inlet of the dirty oil tank, and light dirty oil in the dirty oil tank is discharged through the dirty oil pump.

By adopting the technical scheme, the separated light sump oil intermittently flows to the sump oil tank and is intermittently delivered to a factory sump oil tank area through the sump oil pump.

Preferably, the acidic water pretreatment system further comprises a first water seal device, the first water seal device comprises a raw material acidic water seal device and an adsorption tank, the raw material acidic water seal device is arranged at the tops of the raw material acidic water tank and the raw material acidic water buffer tank, and the adsorption tank is communicated with the raw material acidic water seal device.

Through adopting above-mentioned technical scheme, raw materials acid water tank and raw materials acid water buffer tank top set up raw materials acid water seal ware and adsorption tank to airtight harmful gas's the discharge adsorbs the foul smell component in the release gas, alleviates operation environment's pollution.

Preferably, the heat medium of the reboiler is 1.0MPa steam, the 1.0MPa steam enters from the heat medium inlet of the reboiler, and the steam after heat exchange flows out from the condensed water outlet of the reboiler to the condensed water tank.

By adopting the technical scheme, the bottom of the stripping tower is indirectly heated and stripped by the reboiler so as to ensure that the temperature of the bottom of the stripping tower is about 160 ℃.

Preferably, the acid gas in the stripping tower is discharged from the top of the stripping tower, and the purified water in the stripping tower passes through the secondary heat exchanger, the primary heat exchanger, the purified water air cooler and the purified water cooler in sequence after being discharged from the bottom of the stripping tower.

By adopting the technical scheme, the purified water at the bottom of the stripping tower exchanges heat with the raw material acidic water, and the low-temperature heat is fully utilized.

Preferably, the dephlegmation liquid outlets of the first dephlegmator and the second dephlegmator are both connected with a dephlegmation liquid cooler, and the dephlegmation liquid outlet of the dephlegmation liquid cooler and the dephlegmation liquid outlet of the third dephlegmator are both connected with the raw material acidic water tank.

By adopting the technical scheme, the condensate separated from the first-stage dephlegmator, the second-stage dephlegmator and the third-stage dephlegmator flows back to the raw material acid water tank.

Preferably, a part of the crude ammonia gas discharged from the three-stage partial condenser is discharged to a tail gas incinerator of a sulfur recovery device for incineration, and the other part of the crude ammonia gas is prepared into ammonia water through an ammonia water mixer and an ammonia water cooler and then flows to an ammonia water tank.

By adopting the technical scheme, the crude ammonia gas extracted from the side line is cooled by the primary condensation cooler, the condensate is separated by the primary dephlegmator, the condensate is cooled by the secondary condensation cooler, the condensate is separated by the secondary dephlegmator, the condensate is cooled by the tertiary condensation cooler, and the condensate is separated by the tertiary dephlegmator and then prepared into ammonia water or is sent to a tail gas incinerator of a sulfur recovery device to be burnt.

Preferably, a part of the ammonia water in the ammonia water tank is discharged through an ammonia water pump, and the other part of the ammonia water flows to an ammonia water preparation pump; and discharging one part of the ammonia water discharged from the outlet of the ammonia water preparation pump to the ammonia water mixer, and discharging the other part of the ammonia water to the raw material acid water tank.

By adopting the technical scheme, one part of the ammonia water in the ammonia water tank passes through the ammonia water pump discharge device, and the other part of the ammonia water can be circulated to the ammonia water mixer through the ammonia water preparation pump to obtain the ammonia water or flows back to the raw material acid water tank.

Preferably, a second water seal device is arranged at the top of the ammonia water tank, and the second water seal device is an ammonia water seal device.

Through adopting above-mentioned technical scheme, the top of aqueous ammonia jar sets up aqueous ammonia water seal ware to airtight harmful gas's the discharge.

Therefore, the invention has the following advantages:

(1) the invention adopts a reliable single-tower pressurization side-draw steam stripping process, mainly consumes 1.0MPa steam, electricity, circulating water and the like, and reduces the energy consumption by more than 40 percent compared with double-tower steam stripping;

(2) the raw material acidic water seal device and the adsorption tank are arranged at the tops of the raw material acidic water tank and the raw material acidic water buffer tank to seal the discharge of harmful gas, so that malodorous components in released gas are adsorbed, and the pollution to the operating environment is reduced;

(3) the raw material acid hydrothermal feed enters the stripping tower after the temperature of the raw material acid hydrothermal feed reaches about 150 ℃ through primary heat exchange of purified water, side gas heat exchange and secondary heat exchange of purified water, and low-temperature heat is fully utilized.

Drawings

FIG. 1 is a schematic diagram of an embodiment of the present invention;

FIG. 2 is a schematic diagram of the construction of the acid water pretreatment system of the present invention;

FIG. 3 is a schematic diagram of the sour water stripping system of the present invention;

FIG. 4 is a schematic view showing the structure of an ammonia gas treating system according to the present invention.

Illustration of the drawings: 1-raw material acidic water filter, 2-raw material acidic water degassing tank, 3-raw material acidic water tank, 4-raw material acidic water pressure pump, 5-raw material acidic water degreaser, 6-raw material acidic water buffer tank, 7-raw material acidic water feed pump, 8-cold feed cooler, 9-first heat exchanger, 10-first condensation cooler, 11-second heat exchanger, 12-reboiler, 13-stripping tower, 14-cold feed line, 15-hot feed line, 16-first partial condenser, 17-second condensation cooler, 18-second partial condenser, 19-third condensation cooler, 20-third partial condenser, 21-ammonia water mixer, 22-ammonia water cooler, 23-ammonia water tank, 24-ammonia water pump, 25-dirty oil tank, 26-dirty oil pump, 27-raw material acidic water seal device, 28-adsorption tank, 29-condensation water tank, 30-purified water air cooler, 31-purified water cooler, 32-condensate cooler, 33-ammonia water preparation pump and 34-ammonia water seal device.

Detailed Description

The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings.

As shown in fig. 1, the invention provides a technical scheme of an aromatic hydrocarbon stripper acidic water recycling system, which comprises an acidic water pretreatment system, an acidic water stripping system and an ammonia gas treatment system.

As shown in fig. 2, the acidic water pretreatment system comprises a raw acidic water filter 1, a raw acidic water degassing tank 2, a raw acidic water tank 3, a raw acidic water pressurizing pump 4, a raw acidic water degreaser 5, a raw acidic water buffer tank 6 and a raw acidic water feed pump 7 which are connected in sequence through pipelines, wherein the output end of the raw acidic water feed pump 7 is connected to an acidic water stripping system; and discharging the light oil gas removed from the raw material acidic water degassing tank 2 to a low-pressure gas pipe network or a gas holder.

The acidic water pretreatment system further comprises a dirty oil treatment device and a first water sealing device, wherein the dirty oil treatment device comprises a dirty oil tank 25 and a dirty oil pump 26, dirty oil outlets of the raw material acidic water degassing tank 2, the raw material acidic water tank 3 and the raw material acidic water degreaser 5 are all connected with an inlet of the dirty oil tank 25, and light dirty oil in the dirty oil tank 25 is discharged through the dirty oil pump 26; the first water seal device comprises a raw material acidic water seal device 27 and an adsorption tank 28, the raw material acidic water seal device 27 is arranged at the tops of the raw material acidic water tank 3 and the raw material acidic water buffer tank 6, and the adsorption tank 28 is communicated with the raw material acidic water seal device 27.

As shown in fig. 3, the sour water stripping system comprises a cold feed cooler 8, a primary heat exchanger 9, a primary condensing cooler 10, a secondary heat exchanger 11, a reboiler 12 and a stripping tower 13, the output end of a raw sour water feed pump 7 is connected with a cold feed line 14 and a hot feed line 15, the cold feed line 14 is connected with the top of the stripping tower 13, the hot feed line 15 is connected with the middle of the stripping tower 13, the cold feed cooler 8 is arranged on the cold feed line 14, the primary heat exchanger 9, the primary condensing cooler 10 and the secondary heat exchanger 11 are arranged on the hot feed line 15 in sequence, the reboiler 12 is arranged at the lower part of the stripping tower 13, the side outlet of the stripping tower 13 is connected with the primary condensing cooler 10, and the output end of the primary condensing cooler 10 is connected to an ammonia gas treatment system; the heat medium of the reboiler 12 is 1.0MPa steam, the 1.0MPa steam enters from the heat medium inlet of the reboiler 12, and the steam after heat exchange flows out from the condensed water outlet of the reboiler 12 to the condensed water tank 29; the acid gas in the stripping tower 13 is discharged from the top of the stripping tower 13, and the purified water in the stripping tower 13 passes through the secondary heat exchanger 11, the primary heat exchanger 9, the purified water air cooler 30 and the purified water cooler 31 in sequence after being discharged from the bottom of the stripping tower 13.

As shown in fig. 4, the ammonia gas treatment system comprises a first-stage dephlegmator 16, a second-stage condensation cooler 17, a second-stage dephlegmator 18, a third-stage condensation cooler 19, a third-stage dephlegmator 20, an ammonia water mixer 21, an ammonia water cooler 22 and an ammonia water tank 23 which are connected in sequence through pipelines, and ammonia water is discharged through an ammonia water pump 24 at the outlet of the ammonia water tank 23; the dephlegmation liquid outlets of the first-stage dephlegmator 16 and the second-stage dephlegmator 18 are both connected with a dephlegmation liquid cooler 32, the dephlegmation liquid outlet of the dephlegmator 32 and the dephlegmation liquid outlet of the third-stage dephlegmator 20 are both connected with a raw material acid water tank 3, a part of crude ammonia gas discharged from the third-stage dephlegmator 20 is discharged to a tail gas incinerator of a sulfur recovery device for incineration, the other part of crude ammonia gas is prepared into ammonia water through an ammonia water mixer 21 and an ammonia water cooler 22 and then flows to an ammonia water tank 23, a part of ammonia water in the ammonia water tank 23 is discharged through an ammonia water pump 24, and the other part of ammonia water can be circulated from an ammonia; the top of the ammonia tank 23 is provided with a second water seal device, which is an ammonia water seal device 34.

A system for recycling acidic water of an aromatic hydrocarbon stripping tower of a certain refinery aims to comprehensively treat the acidic water generated by a device for producing olefin by catalyzing heavy oil at 80 ten thousand tons per year, considers the requirement of factory development based on the principles of centralized treatment of pollutants, reduction of operation cost, investment saving, small occupied area and the like, and considers the change of the processing amount of an upstream device and the sulfur content of processed raw oil.

The system adopts a single-tower pressurized side-draw steam stripping process, the quality of purified water meets the recycling requirement of an upstream device, the byproduct ammonia water is supplied to a catalytic device and a sulfur recovery part for ammonia injection, and the redundant ammonia gas is sent to the sulfur recovery part for incineration; the method is characterized in that a raw material acidic water efficient oil removal facility is arranged, the operation of a main stripping tower is improved, and the hydrocarbon content of acidic gas at the top of the tower is reduced; a reboiler at the bottom of the stripping tower adopts 1.0MPa steam as a heat source; the top of the stripping tower: temperature 40 ℃, pressure 0.50mpa (g), bottom of stripping column: temperature 160 ℃ and pressure 0.53MPa (G); acid water stripping tower: specification phi 800/1400/1600 x 50645, the tower body is made of carbon steel and is subjected to integral heat treatment, and 49 layers of high-performance tower plates are arranged in the tower.

The process flow of the aromatic hydrocarbon stripping tower acid water recycling system comprises the following steps: acid water from the outside of the device enters a raw material acid water degassing tank 2 through a raw material acid water filter 1, the separated light oil gas is sent to a low-pressure gas pipe network or a gas holder, the degassed acid water enters a raw material acid water tank 3 for sedimentation and deoiling, then enters a raw material acid water deoiler 5 for further deoiling after being pressurized by a raw material acid water pressure pump 4, the separated light sump oil intermittently flows to a sump oil tank 25 and is intermittently sent to a factory sump oil tank area through a sump oil pump 26, the deoiled acid water enters a raw material acid water buffer tank 6 and is pressurized by a raw material acid water feed pump 7, a part of raw material water is cooled by a cold feed cooler 8 and is used as cold feed of a stripping tower, the rest raw material water passes through a primary heat exchanger 9, a primary condensing cooler 10 and a secondary heat exchanger 11 and then enters a first layer tower tray of a stripping tower 13 as hot feed, the tower bottom is indirectly heated and stripped by a reboiler 12 to ensure the temperature of 160 ℃, the purified water at the bottom of the stripping tower exchanges heat with the raw material water and is sent out of the device, and the acid gas at the top of the stripping tower 13 is sent to a sulfur recovery part; the raw material acidic water seal 27 and the adsorption tank 28 are arranged at the tops of the raw material acidic water tank 3 and the raw material acidic water buffer tank 6 to seal the discharge of harmful gas, so that malodorous components in released gas are adsorbed, and the pollution to the operating environment is reduced; crude ammonia gas extracted from the side line of the 17 th layer of the tower tray of the stripping tower is cooled by a first-stage condensation cooler 10, a first-stage dephlegmator 16 separates condensate, a second-stage condensation cooler 17 cools, a second-stage dephlegmator 18 separates condensate, a third-stage condensation cooler 19 cools, and a third-stage dephlegmator 20 separates condensate and then prepares ammonia water or sends the ammonia water to a tail gas incinerator of a sulfur recovery device to be burnt.

It should be understood that this example is only for illustrating the present invention and is not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.